Improvements in automatic bag sealing machines

摘要

A power driven machine for automatically sealing bags with adhesive tape includes a holder for holding a roll 1 of adhesive tape, the adhesive tape having an opaque marker attached near to its inner end, a tying station 4a, 4b for applying a strip of adhesive tape from the roll 1 around the gathered neck of the bag, and a light source and a light detector 9 which are mounted adjacent the path of the tape from the roll 1 to the trying station 4a, 4b are to detect the approach or passage of the opaque marker indicating the exhaustion of the roll 1 and send a signal to means 12 which stops the machine. The bag sealing machine may also include a supply of paper tape 5 to provide easy opening tabs on the adhesive tape ties and may include a hot foil blocking type printer 2 to print information onto the adhesive tape and hence onto the ties. In both or either of these cases further light source and light detector pairs 10 and 11 may be provided and arranged to stop the operation of the machine upon exhaustion of the paper tape or foil.